Screening On The Cellulose-decomposing Microorganisms And Study On Mechanisms

Cellulose is the most abundant organic raw material in the world, and it is the only renewable resource that is available in large quantities. Presently, only a few types of cellulose are utilized efficiently, most of cellulose are wasted and cause environment pollution. The waste liquid from pulp&paper mill have a lot of cellulose. In order to make full use of cellulose and clear the waste liquid from pulp&paper mill, experiments were carried out to study the screening of high-activity cellulose-degrading bacteria and study on their growth and fermentation characterization.Three strains of high-activity cellulose-degrading bacteria were isolated and screened from nature . And the target strains Z-l was gained because of higher biomass in this paper. The growth characterization were studied and results as follows: Its biomass was the largest when being cultivated for 96 hours; The optimal pH of growth was 7.0; and the most suitable temperature was 26? ~34?.Several single factors that can affect the cellulase activity was studied in this paper. The result shows: temperature, inoculation volume, cutivation time , initial pH, aeration,e.t. have great effect on cellulase productivity. 25?, pH7.0, 4% inoculation volume, the age of 48 hours, volume of 100mL are the optimum conditions of producing cellulase.The orthogonal experiment showed that the medium with CMC-Na/bran=1:1 as carbon source, albumen and (NH4)2SO4 as nitrogen source was optimal. The maximum activity was reached at 25 ?, pH7.0 and 125mL volume. The maximum of CMCase was 734U.The paper provides a good way to guide how to screen the high-activity cellulose-degrading bacteria. The high-activity cellulose-degrading bacteria can be applied in wastewater treatment.